Machine for treating granular material



July 1, 1930.

H. BEHRENS MACHINE FOR TREATING GRANULAR MATERIAL 2 Sheets-Sheet 1 Filed March 27, 1929 [1:9] Inventor.-

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July 1, 1930. H. BEHRENS MACHINE FOR TREATING GRANULAR MATERIAL Filed March 27, 1929 2 Sheets-Sheet 2 [771/621 Jar.-

Patented July 1, 1930 UNITED STATES HERMANN' BEHRENS, I OF HANOVER, GERMANY, ASSIGN'OR OF ONE-HALF TO MAS-- PATENT OFFICE CHINEN- UND WERKZEUGFABBIK KABEL VOGEL &; SCHEMMANN A.-G.,. OF KABEL,

GERMANY, A GEBMAN COMPANY Application filed March 27, 1929, Serial No.

ticularlymoulding sand, by means of which either moulding sand that has been used or moulding sandcoming fresh from the pits may be loosened and cleaned in order to get it ready for use. p

The object of the invention is to provide 'a machine for the purpose stated, .which thoroughly exposes the sand to the air and at the same time consumes little power, is

subject to but .slight wear of the working parts, that owingto the construction of the machine are moreover not liable to breakage, mechanically separates the impurities from the sand and is not liable to injure the attendants by the projection of solid particles. Moreover the supply of sand to the machine is ,easily effected in a simple manner and the sand. ready for use is dis charged behind themachine, but not under it, so that the machine may be moved away with out obstruction from the sand that has been vention are illustrated by way of example in the accompanying drawing.

Figure 1 shows the machine in cross section.

Figure 2 is a longitudinal section on the line AB of Figure 1.

Figure 3. shows the main features of the machine diagrammatically in cross section. Figure 4 is an elevation of the screenmg evice.

Figure 5 is a cross section of the screening device on the line C-D of Figure 1.

Figure 6 is a perspective view of the throttling valve with its guide rods.

Figure 7 is a diagrammatic view similar 350,327, and in Germany October 11, 1927.

to Figure 3 but showing a modified, shape of one feature.

Figure 8 shows a second construction of the machine in cross section.

Figure 9 is a longitudinal section of this machine on the line EF of Figure 8 and Figure 10 shows an elevation of a third construction of the machine, similar to Figure 8, but stationary.

The spindle u of a drum a, Figure 1, sup ported in bearings 12 on the frame or bed 0, is provided at its periphery with knives or ledges a presenting edges disposed parallel to its axis. There are preferably only a few of these ledges, four being shown in the constructions illustrated, and from each .ledge to the next extends a covering or lagging plate or sheet 0 which starts at the back of a ledge, close to its outer edge and terminates at the foot of the next ledge. The ends of the cover plates 0 are secured by means of strips 0" that are disposed parallel to the ledges c and like the cover plates 0 are fixed to the circularjend plates 0 of the drum 0.

The drum a that is mounted on the bed freely, viz without a casing, rotates in the direction of the arrow or clockwise and above the same and on the rising side of the drum as viewed in Figure 1 is mounted a hopper d, and adjacent to the hopper and between it and the vertical central line is pivotally mounted a throttling valve .9 that iscarrie'd by two rods f connected to the valve by means of the brackets 6', Figure 6. The rods 7 are situated outside the hopper 03 and the brackets 6' project through arc-shaped slots in the lateral walls of the hopper, the bearings of the rods f being secured to the rear wall. The throttling valve e is. formed as an angular plate and its main portion directed towards the hopperv with the main portion while stops e" limit the downward movements of the valve e. The tangent I (Figure 3) to the circumference of the drum at the "point-of. discharge from the hop er (1 strikes the lower surface of the thrott 'ng valve.

The lateral walls is of the hopper are ex- 'arra e so as to permit each wire a sh ht later movement along the rods m. he two rakes are pivoted. to the-walls k by means of the upper rods m and they bear against ledges n mounted on the walls 1:, the wlres'l of one rake being arranged behind the intervals or gaps between the wires Z of the other rake.

The wallsk are connected together at the tog by a plate 7: that forms a roof and above w ich is mounted a shaking screen or sieve h carried on four vertical rods q that oscillate on two spindles a: extendin fromone rod to the other on the bed 0 of t e machine.

To oscillate the shaking screen h gear wheels 8 and t are employed the former. of which is secured to the spindle it while the wheel t drives by means of a crank a connecting rod r that enga es with one of the rods The bottom 11 o the shaking screen h is o liquely disposed so that the sand passing through the. screen slides down into the hopper. I 1

e bed 0 of the machine also sup orts an electric motor 1:, the shaft of wh1c is arranged in line with the spindle w and is coupled to it by a couplin c. The bed is rovided with front whee s p, as shown in igure 2, on which it may be supported, an with pelled or, as shown in Figure 10, with egs so that it'is stationary.

The drum a driven by the electricmotor 12 rotates in the direction of the arrow shown in Figure 1 so that the sand discharged from the hopper d and cleaned in the shaking screen It is struck by the rotating led c and projected against the throttlin vafse e.

As a narrow assage is forme between the throttlilrlif v ve and the passing ledges the sand w' be rubbedby the ledges 'alon the surface of the throttlin valve whic 'elds upwardly to allow ti arg'e hard objects. Owing to the decreasing size of the passage between the throttling valve and the drum in the direction of rotation of the drum, thewsand will be ressed b the throttling valveagainst the le drum so that they can strike and grind downthesand.- f

The sand flies freel throu h the air bethe throttling va ve llliti it strikes the wires Z of the first rake that keeps back'large particles, more particularlyiron articles, which fall down to the bottom. e coarse particles which have assed through one rake, are held up by t e other rake on ace passage ofges of- I said drumv which orms with count of the relative staggering of the wires, the slight movement of t e wires along the rods preventing sticking of the sand to the wires. Behind the two rakes which in this manner jointlyvform what may be regarded as an iron catcher, the sand falls down to the bottom and is then ready for use.

During this treatment of the sand lumps are broken up, the sin le sand particles are separated, exposed to t e air and freed from foreign substances. The sand falling freely down is therefore loose and uniformly interpenetrated by air-filled pores.

The depth of the kmves or ledges 0 and the speed of rotation of the drum are interdependent in such a manner that the sand inthe hopper d has time, between the passing of one ledge and the passing of the followingone, to fall down almost to the end of a covering plate c. Each knife or ledge therefore deals with a quantity of sand to almost its. full depth and treats it in the manner described. This gives a circumferential speed of-the drum of about 20 meters per second. The position of the throttling valve e relatively to the tangent I, Figure 3, prevents part of the sand from being forced'back into the hopper. The outer edge of the knives or led es is preferably smooth but they may also be serrated. The shape of the covering plates of the drum revents the formation of air eddies behin the rotating knives or ledges.

In the construction according to Figure 7 the throttling valve '6 is formed inte al with the lower part of the hopper d and 0th are mounted in the bearings g on the bed of handle by hi h it may b ]the machine. The result of this is that the hopper d participates in the yieldin movements of the throttling valve whic tends to facilitate the discharge of the sand contained in the hopper and thereby ensure the smooth working of the subsequent operations.

In the construction according to Figures 8 and!) the electric motor 3 is mounted in the interior of the drum a but it is not of the usual construction with the rotor inside the shaking screen is dispensed with.

m e or treating anular material, com a hopper, a El um rotat' under the. op r with radial ledges aralle to the o the drum and a yie dingly mounted throt valve above periphery of the drum: a passage that decreases in size in the direction of rotation of the drum.

but has an outside rotor and an inside .at the back of one ledge close to its outer ed e and-terminate at the foot of the next le ge.

5. A machine according to claim 1, in

which the drum is mounted treely on the bed of the machine.

6. A machine according to claim 1, in which a. motor with an inner stator and outer rotor is mounted in the interior of the drum in such a manner that the rotor of the motor is rigidly secured to the drum.

7. A machine according to claim 1, in which a shaking ,sieve or screen oscillated by the machine is mounted above the hopper,

8. A machine according to claim 1, in

which an iron catcher constituted by several 1 rakes with straight wires slightly movable along the rods on which they are threaded and staggered relatively to one another is situated in the path of the material treated by the drum.

.9. A machine according to claim 1, in which the, lower portion of the hopper is formed integral with the yieldingly mounted throttling valve.

In testimony whereof I have afiixed my signature.

HERMANN BEHRENS. 

